Investigation of demographic, clinical, laboratory features, and outcomes of children with serum sickness hospitalized in a hospital

Background & Aims: Serum sickness is a type 3 hypersensitivity reaction caused by the injection of foreign proteins, serums, and nonprotein medications.This study investigated the demographic, clinical, and laboratory characteristics, along with outcomes, of patients with serum sickness hospitalized at Shahid Motahari Hospital, Urmia, from March 2017 to February 2021. Materials & Methods:This descriptive cross-sectional study included 67 patients diagnosed with serum sickness based on a recent history of exposure to an antigenic substance.Demographic, clinical, paraclinical data, and disease outcomes-including hospital stay length, ICU admission history, treatment response, mortality, and information regarding the potential cause of the disease-were collected from patient records, recorded in a checklist, and analyzed using SPSS statistical software version 22. Results:Arthralgia was present in 20 patients (29.9%), gastrointestinal complaints in nine children (13.4%), headaches in eight children (11.9%), muscle pain in 18 children (26.9%), arthritis in 14 children (20.9%), and urinary symptoms in one child (1.5%).The most frequent cause of serum sickness was phenobarbital, identified in 26 patients (38.8%), followed by cefixime in nine patients (13.4%), azithromycin in six patients (9%), ceftriaxone in five patients (7.5%), and co-amoxiclav in four patients (6%).Additionally, leukocytosis was found in 23 patients (34.3%), 32 patients (47.8%) had a positive C-reactive protein (CRP), 32 patients (47.8%) had an elevated erythrocyte sedimentation rate (ESR), same as sedimentation rate, and elevated aspartate aminotransferase (AST) and alanine transaminase (ALT) were detected in 4 patients (6%) each. Conclusion:Clinically, serum sickness was most commonly associated with fever, skin rashes, muscle pain, and changes in paraclinical findings in patients.